In microsurgical applications, a surgical laser may be used in conjunction with a surgical microscope. Small laser heads have been developed which can mount directly to a surgical microscope usually by attaching directly to the standard microscope dovetail mount or to the standard microscope objective lens mount. Two types of microscope mounted lasers have been used. Some are mounted with the laser extending at about 90.degree. with respect to the microscope optical axis and others are mounted with the laser extending parallel to the microscope optical axis.
The laser and its optical train are configured in a package which is generally quite sizeable and in certain circumstances interfere with the surgical procedure or with the movement of the microscope and its attached laser about the surgical field. Sometimes the laser will interfere with the view of the surgical site or will otherwise interfere with the access to the surgical site by the various personnel required to do the operation. Under some conditions a laser mounted at 90.degree. to the optical axis offers advantages, while in other conditions, the parallel mounted laser provides advantages.
In the past, before compact lasers were mounted directly to the microscope, the laser was positioned remote from the microscope and the laser beam was delivered to the microscope through the articulated arm on which the microscope was supported. Such lasers are shown, for example, in U.S. Pat. No. 4,309,998 and U.S. Pat. No. 4,122,853. To permit transmission of the laser energy through the articulated arm, the arm must be hollow and a series of special joints and mirrors are used to deliver the beam to the surgical site. Every time the articulated arm is moved, there is a possibility that the lenses in the joints can become misaligned. If a large number of lenses are used the misalignments of the multiple lenses can require constant readjustment of the articulated arm and laser beam path.
It would be desirable to have a compact laser mounted directly to a microscope which could be swiveled from a position aligned perpendicular to the optical axis of the microscope to a position aligned parallel to the optical axis of the microscope or to a variety of other positions. It would further be useful to have such a swiveling laser mount which would not need constant realignment and adjustment of the lenses in the assembly.
It is also desirable for a user to have access to the objective lens of the microscope during use for cleaning or other purposes.
Additionally, it is desirable for a user to be able to set and recall various laser spot sizes for a variety of surgical tasks.